1. Field of the Invention
The present invention relates generally to internal components of motors, and more particularly to an insulating member for a carbon brush holder used in a motor.
2. Description of the Related Art
A conventional insulating member 60 for a carbon brush holder, as shown in FIG. 5, is comprised of a main body 61 and a cover member 62. The main body 61 has a first end 63 and a second end 64 respectively at two ends thereof, and a through hole 65 running through the first and second ends 63 and 64. The through hole 65 is provided with a first section 66 abutting the first end 63 for holding a copper member (not shown) of the carbon brush, and a second section 67 abutting the second end 64. The second section 67 of the through hole 65 is provided with an internal thread 70 having a spiral thread tooth 71, which has two bevels 72 that have the same distance between a peak and a bottom of the thread tooth 71. The cover member 62 is provided with an external thread 73 corresponding to the internal thread 70 of the main body 61 around a periphery thereof to be threadedly fitted into the second section 67 of the through hole 65 for stopping an end of a spring potentially mounted in the insulating member 60.
However, the conventional insulating member 60 has drawbacks as recited below. Both of the internal thread 70 of the main body 61 and the external thread 73 of the cover member 62 are conventional mechanical threads, such that looseness is generated between them during the process of screwing, and then tightness is generated between them while they are fully threadedly fitted with each other. Hence, when the insulating member 60 is applied inside the motor, the cover member 62 and the main body 61 easily get rid of tightness therebetween subject to the vibration of the motor to further cause the cover member 62 to slip off the main body 61, and additionally, the operator is uneasily aware of such condition during the operation, potential danger and harm against the user will be occurred.